Deny is probably the least fancy.
renounce, repudiate
contradict, disagree, refubb, negate, rebut, refute, renounce, reject, retract, repudiate, recant, disclaim
The suffix for "repudiate" is "-ate".
He was forced to repudiate a statement he had made before he had all the information
If you say that I told you, I will repudiate that claim.
Repudiate means to refuse to be associated with or accept. She is going to repudiate her cable bill because the amount is wrong.
The evidence itself will repudiate your ridiculous fabrication.
People from the group would later repudiate the statements they made there. Various factors may encourage a country to repudiate its agreements with foreign investors.
He wins most debates because his arguments are difficult to repudiate. He not only quit the party, but proceeded to repudiate his earlier political position.
Although I am a citizen of Canada, I repudiate the misguided policies of the Canadian government.
"repudiate"
The witness repudiated her earlier testimony at the trial. His family repudiated him after he became a criminal.